Against the background of increasingly interlinked production processes and their standardization in the industry, the problem that is nowadays the prime concern in the production of machine tools is that of also incorporating in this process the computer systems that are necessary for activating the machine tools. In this respect, one aim is to provide, to the extent technically possible, standardized machine control systems, offering the user greatest possible uniformity of the machine control parameters for the products from his range of workpieces—for instance when changing an actual machine type or else for improved data storage and archiving.
Such initiatives have already been pursued for some time for various types of machine tools.
For bevel gear cutting machines there are for instance solutions to this in which the relevant machine control parameters of an entire machine family are combined in a standardized data model with all the axes to be activated that come into consideration in the machine family, which then, in individual cases, is replicated on the respective machine actually concerned —to the extent to which this is possible, that is to say the axes activated by the machine control parameters are also actually present.
One problem of these systems is, however, that the standard data model created by them for the machine control parameters also entails great risks for the operational reliability of the machine tools respectively activated with them. While in the case of a non-standard data model there is no risk of using the machine control parameters to activate a machine type which is not suitable for these parameters, because it cannot even read the corresponding format, or at least not process it, this is no longer ruled out in the case of the standardization mentioned above. Rather, here it is the case that all the machine types can read in the machine control parameters in their standard format and also process them for their control; however, here it is not ensured that this processing then always leads to an appropriate working result on the machine. Indeed, more troubling still, it is still possible for machine control parameters which have been generated for one machine type 1 to be incorrectly sent to a machine of type 2, which then processes them and thereby controls its axes in such a way as to cause irreparable damage to the machine itself or even personal injury, for instance as a result of electric cables being severed by cutting tools improperly controlled in this way.
Such improper activation can be avoided for instance by adding to the machine control parameters a machine address, which specifies the machine that can be activated with the aid of the machine control parameters, and by setting up the machines in such a way that they first check from this added machine address whether the machine control parameters are also actually suitable for them. Such a procedure presupposes, however, that the machine control parameters protected in this way are also actually in an unchanged form when they reach the machine from the source from which they originate. This cannot always be ensured, however. Rather, it is the case that, once generated, parameters of this type are easy to change. For instance, it is possible that machine control parameters are generated for a specific workpiece and a specific machine, but this machine is not available at the planned production time. If another machine is provided instead, one which is capable in principle of processing the machine-independent format of the machine control parameters, but for different limit values and under different boundary conditions in terms of safety than those which apply to the machine originally planned for use, there is a great temptation simply to use the machine control parameters for this machine although they are not enabled for it, in that, instead of the original machine address of the machine that is not available, now the address of the other machine, which although available for these control parameters has not been enabled, is entered—for instance by means of an editor.
Experience shows that, in today's production plants, which are under strong pressure to produce results, such a procedure breaching safety functions is not uncommon.